A DBT sponsored Two day Workshop on advanced and Skill based technologies in
Microbial Identification for students of the Biological Sciences was organized
by the Departments of Botany collaboration with Bio Merieux
India Pvt. Ltd on 31st August to 1st September, 2018
The Inaugural session
was started with a Prayer Song followed by blessings of Rev. Fr. Dr. M. Sagayaraj,
Correspondent, ALC and greetings by Rev. Fr. S. Melchior, VP, ALC to the
gathering and advised the students to step out of their shells and study with
an interest to know new things.
The Chief Guest for the Inaugural was Prof. K. Srinivasulu, Head, Department of Biotechnology, Kaneru
Lakshmaiah University. He in sighted the students regarding the importance of
current research and the need for advanced technologies for Biological
students.
Session 2 started with
introduction to the techniques and later on directions on how to use API web
services followed by hands-on training with the techniques of API web.
DEAR STUDENTS SUBMIT THE ASSIGNMENT.
ReplyDeleteGood evening Madam,
ReplyDeleteThis is Shaik.Parveen from NB section,Regd No:172431.I would like to submit my assignment madam.I'm sorry madam i'm unable to send my whole assignment at a time so,i'm sending half-half.
1)Define Embrology?
A:It is the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation.
2)Define Tapetum?
A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei.
3)Define Endothecium.
A:It is remarkably identified by their radially elongated structure.It is rarely multilayered and it produces "fibrous bands" which helps in time of anther dehiscence.
4)Define Microspore?
A:It is formed by microsporogenesis and is responsible for the development of male gametophyte .These are the results of meiosis and usually smaller in size.
5)Define Palynology?
A:The shape,size of microspore or pollengrain.Exine miscrosculpturing and number position character of aperture are great taxonomic importance.These are study under seperate branch called "Palynology".
6)What is Megasporangium and mention its types.
A:Megasporangium is a structure in angiosperm that produces female gametophytes called megaspores.It is borne in pairs at the base of scales of the cones.It is also called "ovule".
TYPES:
a)Orthotropous ovule
b)Anatropous ovule
c)Hemianatropous ovule
d)Campylotropous ovule
e)Amphitropous ovule
f)Circinotropous ovule.
7)Define Monosporic,Bisporic,Tetrasporic embryosacs.
A:Monosporic embryosac:In this type of embryo development 3 megaspores of tetrad gets degenerate and one remain functional and forms embryosac.
Bisporic embyrosac:When 2 megasporic nuclei takespart in the formation of embryosac.Both the nuclei are genetically different.
tetrasporic embryosac:In this type,due to failure of cytokinesis 1 and 2 a four nucleate coenomegaspore tetrad is formed and all 4 nuclei participate in the formation of embryosac.
8)Define Fertilization.Who coined the term "Fertilization".
A:It is a process in sexual reproduction that involves the union of male and female gametes to produce a zygote.The term fertilization was coined by"Oscar Hertwig"(1876).
DEAR Shaik.Parveen,
DeleteGOOD PRESENTATION.
MENTION THE EXAMPLES FOR TYPES OF OVULES.
Good evening Madam ,
DeleteThis is Shaik.Parveen from NB section and my Regd no:172431.This my correction Madam .
6)Megasporangium types
A:orthotropous ovule,eg:Polygonum
Anatropous ovule,eg:Gamopetalae members.
Hemianatropous ovule,eg: Ranunculus
Campylotropous ovule,eg:Legumino Leg.
Amphitopous ovule,eg:Butomaceae.
Circinotropous ovule,eg:Opuntia
Good evening Madam,
ReplyDeleteThis is Shaik.Parveen from NB section,Regd No:172431.This is my 2nd half of my assignment madam.
9)Define a)"Double fetilization" or "Syngamy"and b)"Triple fusion".
A:a)Double fertilization:It is the process in which 2 male gametes fuse with the female gamete and the secondary nucleus respectively to form the zygote and the endosperm.
b)Triple fusion:It can be defined as the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant,giving rise to triploid nucleus called "primary endosperm nucleus"(PEN),which later develops into the endosperm.
10)Define Endosperm and mention its types.
A:The endosperms are very vital parts of the fertilized embryo.An endosperm forms the surrounding tissue of the growing embryo.The primary endosperm nucleus divides repeatedly.It forms polyploidy nutritive tissue called endosperm.These are of 3 types.
They are: 1)Nuclear type
2)Cellular type
3)Helobial type
There is a special type of endosperm called as Ruminate endosperm.
11)Define Ruminate type of endosperm.
A:The condition in which the endosperm is dissected by ingrowths of the seed coat,is a common condition in palms.Ruminate endosperm forms when the seed coat intrudes inward via meristematic growth.
12)Define Helobial endosperm.
A:This type of endosperm occurs in the order "Helobiales".In this case,first division of primary endosperm nucleus is followed by a transverse wall.This wall divide the embryo sac into a small chalazal chamber and a large micropylar chamber.Then the nuclei in each chamber divide by free nuclear divisions.But,there are few nuclear divisions in the chalazal chamber.The endosperm in this chamber degenerate.Walls develop between nuclei in micropylar chamber.It produces cellular endosperm.
13)Mention the differences between Dicot and Monocot embryo.
A:Dicot embryo:An embryo with 2 cotyledons and plumule is distal.Coleoptile,Coleorhiza are absent and Scutellum is also absent.
Monocot embryo:An embryo with 1 cotyledon and plumule is lateral.Coleoptile,Coleorhiza are present and scutellum is present.
14)Define Scutellum.
A:It is the characteristic features of monocot only.The monocot consists of a large and shield shaped cotyledon known as "Scutellum".
15)Define Polyembyrony.
A:The formation of more than one embryo from a single fertilized ovum or in a single seed.
16)Mention the objectives of "Polyembryony".
A:Objectives of Polyembryony:
1)To determine whether polyembryony confers a competitive advantage to V.rossicum.
2)Assess whether this advantage,if present,is more pronounced in intra or interspecific competition, and
3)To determine whether the competitive advantage ,if present,is proportional to the number of embryos per seed.
Thank you Madam.
DEAR Shaik.Parveen,
DeleteGOOD PRESENTATION.
DOUBLE ENTRY NOT REQUIRED
P.Geethika
ReplyDeleteNB:27
1.Define embrology. Name the imminent Indian embryologists.
Ans. Embryology is the branch of biology that studies the prenatal development of gametes, fertilization, and development of embryoes and fetuses. The imminent Indian embryologist is Panchanan Maheswari.
2. What is tapetum?
Ans. Tapetum is the inner most layer of anther wall and completely surrounds the sporogenous tissue.
3. What is Endothecium?
Ans. Endothecium is the layer of cells present inner to epidermis in anther wall.
4. What is Microspore ?
Ans. Microspore is the pollen grain of seed plant.
5. What is Palynology?
Ans. Palynology is the study of external morphology of pollen grains and spores .
6. What is Megasporangium ? Mention the types.
Ans. The formation of four haploid megaspores from megaspore mother cell through meiosis.
The types are :
1. Linear
2. T-shaped
3. Inverted T-shaped
4. Isobilateral
7. Define Monosporic, Bisporic, Tetrasporic.
Ans. Monosporic: The embryo sac which is derived from only one of the four megaspores. All the nuclei in such embryo sac are genetically identical, because they are derived through mitoses of a single nucleus.
Bisporic: The first meiotic division in megaspore mother cell results in two dyad cells. Only one of the dyad cells undergoes the second meiotic division, but no wall formation occurs. So the resulting two megaspore nuclei contribute in the formation of embryo sac.
Tetrasporic: All the four nuclei of the coenomegaspore take part in the formation of tetrasporic embryo sac. In this type there is no wall foramtion.
8. Define fertilization. Who coined the term syngamy.
Ans. The fusion of male gamete with the female gamete is known as fertilization. Syngamy term was coined by Stras burger(1884).
9. Define Double fertilization and Triple fusion.
Ans. In angiosperms, the two main gametes relased in to the embryo sac take part in fertilization. One of the sperm fuses with the egg nucleus resulting in a zygote. The other male gamete fuses with the secondary nucleus forming primary endosperm nucleus. This is known as double fertilization.
Triple fusion: The union of one male nucleus with secondary nucleus is known as triple fusion. As it involves the union of three nuclei the resultant is called primary endosperm nucleus.
10. What is Endosperm and its types?
Ans. Endosprerm is most common nutritive tissue for the developing embryos in angiosperms.
There are three types:
1. Nuclear Endosperm
2. Cellular Endosperm
3. Helobial Endosperm
11. What is Ruminate Endosperm?
Ans. Mature endosperm with some degree of irregularity and unevenness in its surface contour is called Ruminate endosperm.
12. What is Helobial Endosperm?
Ans. The primary endosperm nucleus moves towards the chalazal end of the embryo sac. Here it divides to form a large micropylar chamber and a small chalazal chamber.
13. Difference between dicot and monocot embryos.
Ans. Dicot: There are two cotyledons attached to embryonal axis. Coleoptile is absent. Scutellum is absent.
Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present.
14. What is Scutellum?
Ans. The single cotyledon of a monocot embryo is known as Scutellum
DEAR GEETHIKA,
DeleteGOOD PRESENTATION.
MENTION THE EXAMPLES FOR TYPES OF ENDOSPERMS.
P.Geethika
ReplyDeleteNB:27
15. What is Polyembryony ?
Ans:The occurence of more than one embryo in a seed is known as polyembryony.
16. Mention the objectives of polyembyrony.
Ans:1. cleavage of the embryo.
2. formation of embryosacs form other cells of the embryosacs.
3. for the development of one than one embryosac within the same ovule.
Dear GEETHIKA,
DeleteGOOD PRESENTATION, DOUBLE ENTER IS NOT REQUIRED.
I am teja raghu.
ReplyDeleteNB-25.
Submitting botany assaignment.
the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation.
2)Define Tapetum?
A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei.
3)Define Endothecium.
A:It is remarkably identified by their radially elongated structure.It is rarely multilayered and it produces "fibrous bands" which helps in time of anther dehiscence.
4)Define Microspore?
A:It is formed by microsporogenesis and is responsible for the development of male gametophyte .These are the results of meiosis and usually smaller in size.
DEAR TEJA,
DeletePLEASE WRITE YOUR NAME PROPERLY.
EXPLAIN ENDOTHECIUM PROPERLY
WRITE THE STRUCTURE OF THE MICROSPORE
I am teja raghu (nb_25)
ReplyDelete5. What is Palynology?
Ans. Palynology is the study of external morphology of pollen grains and spores .
6. What is Megasporangium ? Mention the types.
Ans. The formation of four haploid megaspores from megaspore mother cell through meiosis.
The types are :
1. Linear
2. T-shaped
3. Inverted T-shaped
4. Isobilateral
7. Define Monosporic, Bisporic, Tetrasporic.
Ans. Monosporic: The embryo sac which is derived from only one of the four megaspore.
Bisporic: The functional megaspore is developed from two megasporenuclei.
Tetrasporic: All the four nuclei of the take part in the formation of tetrasporic embryo sac.
8. Define fertilization. Who coined the term syngamy.
Ans. The fusion of male gamete with the female gamete is known as fertilization. Syngamy term was coined by Stras burger(1884).
9. Define Double fertilization and Triple fusion.
Ans. In angiosperms, the two main gametes relased in to the embryo sac take part in fertilization. One of the sperm fuses with the egg nucleus resulting in a zygote. The other male gamete fuses with the secondary nucleus. This is known as double fertilization.
Triple fusion: The union of one male nucleus with secondary nucleus is known as triple fusion. As it involves the union of three nuclei the resultant is called primary endosperm nucleus.
10. What is Endosperm and its types?
Ans. Endosprerm is most nutritive tissue for the developing embryos in angiosperms.
There are three types:
1. Nuclear Endosperm
2. Cellular Endosperm
3. Helobial Endosperm
11. What is Ruminate Endosperm?
Ans. Mature endosperm with some degree of irregularity and unevenness in its surface is called Ruminate endosperm.
12. What is Helobial Endosperm?
Ans. The primary endosperm nucleus moves towards the chalazal end of the embryo sac. Here it divides to form a large micropylar chamber and a small chalazal chamber.
13. Difference between dicot and monocot embryos.
Ans. Dicot: There are two cotyledons attached to embryonal axis.
Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present.
14. What is Scutellum?
Ans. The single cotyledon of a monocot embryo is known as Scutellum
DEAR TEJA,
DeleteEXPLAIN HELOBIAL ENDOSPERM PROPERLY
I am B.Ravi teja Nb_60
ReplyDelete.Define embrology. Name the imminent Indian embryologists.
Ans. Embryology is the branch of biology that studies the prenatal development of gametes, fertilization, and development of embryoes and fetuses. The imminent Indian embryologist is Panchanan Maheswari.
2. What is tapetum?
Ans. Tapetum is the inner most layer of anther wall and completely surrounds the sporogenous tissue.
3. What is Endothecium?
Ans. Endothecium is the layer of cells present inner to epidermis in anther wall.
4. What is Microspore ?
Ans. Microspore is the pollen grain of seed plant.
5. What is Palynology?
Ans. Palynology is the study of external morphology of pollen grains and spores .
6. What is Megasporangium ? Mention the types.
Ans. The formation of four haploid megaspores from megaspore mother cell through meiosis.
The types are :
1. Linear
2. T-shaped
3. Inverted T-shaped
4. Isobilateral
7. Define Monosporic, Bisporic, Tetrasporic.
Ans. Monosporic: The embryo sac which is derived from only one of the four megaspores. All the nuclei in such embryo sac are genetically identical, because they are derived through mitoses of a single nucleus.
Bisporic: The first meiotic division in megaspore mother cell results in two dyad cells. Only one of the dyad cells undergoes the second meiotic division, but no wall formation occurs. So the resulting two megaspore nuclei contribute in the formation of embryo sac.
Tetrasporic: All the four nuclei of the coenomegaspore take part in the formation of tetrasporic embryo sac. In this type there is no wall foramtion.
8. Define fertilization. Who coined the term syngamy.
Ans. The fusion of male gamete with the female gamete is known as fertilization. Syngamy term was coined by Stras burger(1884).
9. Define Double fertilization and Triple fusion.
Ans. In angiosperms, the two main gametes relased in to the embryo sac take part in fertilization. One of the sperm fuses with the egg nucleus resulting in a zygote. The other male gamete fuses with the secondary nucleus forming primary endosperm nucleus. This is known as double fertilization.
Triple fusion: The union of one male nucleus with secondary nucleus is known as triple fusion. As it involves the union of three nuclei the resultant is called primary endosperm nucleus.
10. What is Endosperm and its types?
Ans. Endosprerm is most common nutritive tissue for the developing embryos in angiosperms.
There are three types:
1. Nuclear Endosperm
2. Cellular Endosperm
3. Helobial Endosperm
11. What is Ruminate Endosperm?
Ans. Mature endosperm with some degree of irregularity and unevenness in its surface contour is called Ruminate endosperm.
12. What is Helobial Endosperm?
Ans. The primary endosperm nucleus moves towards the chalazal end of the embryo sac. Here it divides to form a large micropylar chamber and a small chalazal chamber.
13. Difference between dicot and monocot embryos.
Ans. Dicot: There are two cotyledons attached to embryonal axis. Coleoptile is absent. Scutellum is absent.
Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present.
14. What is Scutellum?
Ans. The single cotyledon of a monocot embryo is known as Scutellum
ENDOTHECIUM, TAPETUM AND MICROSPORE NOTES NOT SUFFICIENT.
DeleteI am B.RaviTeja Nb_60
ReplyDelete15. What is Polyembryony ?
Ans:The occurence of more than one embryo in a seed is known as polyembryony.
16. Mention the objectives of polyembyrony.
Ans:1. cleavage of the embryo.
2. formation of embryosacs form other cells of the embryosacs.
3. for the development of one than one embryosac within the same ovule
I am p.tejaraghu nb-25
ReplyDelete15)Define Polyembyrony.
A:The formation of more than one embryo from a single fertilized ovum or in a single seed.
16)Mention the objectives of "Polyembryony".
A:Objectives of Polyembryony:
1)To develop more number fruits in horticulture
2)To determine whether the competitive advantage ,if present,is proportional to the number of embryos per seed.
DEAR tejaraghu nb-25
DeleteWRITE YOUR NAME PROPERLY
Hi good evening mam this is Vamshi NB-14
ReplyDelete1.define embroyology? name eminent Indian embryologists?
A.It is the branch of biology concerned with the development of new organisms.
samo of the eminent indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)
2.Define Tapetum?
A. Tapetum is the innermost layer of Microsporangium which has dense Cytoplasm.
Functions
i) It release Ubisch bodies.
ii) It provides nutrition to developing Pollen grain.
iii) It release callase enzyme
3.Define Endothecium?
A. This is a transverse section of the anther, the part of the stamen that actually produces the pollen grains. As part of pollen development, the cells lining the anther lumen – a layer known as the endothecium – secretes materials that are essential for the proper maturation of the pollen grains.
it is the fibrous tissue present in the middle layer of anther.
4.Define microspore?
A. microspore refers to the spore produced by sporophytes. It is haploid and gives rise to a male gametophyte. Metagenesis or the alternation of generations involves the alternation of life phases in the life cycle of plants.
5. Define Palaenology?
A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.
6. Define megasporangium? and mention types in it?
A. the structure in certain spore-bearing plants in which the megaspores are formed.
Megasporangia (female sporangia) produce megasporocytes (megameiocytes) that yield megaspores. The sporangia may be borne in specialized structures such as sori in ferns, cones (strobili) in some pteridophytes and most gymnosperms, or flowers in angiosperms.
7. define monosporic, bisporoic, tetrasporic types of embryo sac?
A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
1.monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
2.bisporic type: bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
3. tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.
8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.
9. Define double fertilisation and triple fusion?
A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.
10. Define endosperm? mention the types in it.
A. a nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.
Mam this is Vamshi NB-14 and this is my second part of my assignment
ReplyDelete11. Define ruminate endosperm?
A. the condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms. it is the tissue produced inside the seeds of most of the flowering plants following fertilization. It surrounds the embryo and provides nutrition in the form of starch, though it can also contain oils and protein.
12. Define Helobial type of endosperm?
A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.
13.Mention the differences between dicot and monocot embryos?
A. Monocots : 1. contains one cotyledon
2. usually parallel venation
3. vascular bundales are usually complexy arranged.
4. fibrous root system is present
5. floral parts are usually in multiples of three
Dicots : 1. contains 2 cotyledons
2. usually veins are network like
3. vascular bundles are usually arranged in rings
4. tap root system is present
5. floral parts are usually in the multiples of four or five
14. Define scutellum?
A. The scutellum is part of the structure of a barley and rice seed—the modified seed leaf. The scutellum (from the Latin scutella meaning "small shield") can also refer to the equivalence of a thin cotyledon in monocots (especially members of the grass family)..The scutellum is considered to represent the first leaf or cotyledon.
15. Define polyembryony?
A. the production of more than one embryo from one egg is known as polyembryony. Polyembryony, a condition in which two or more embryos develop from a single fertilized egg, forming what in humans is known as identical twins. A common phenomenon in many plant and animal species, polyembryony occurs regularly in the nine-banded armadillo, which usually gives birth to four identical young.
Hi good evening mam this is Sri Ram NB 55
ReplyDelete1)Define embryology? Name the eminent Indian embryologist
the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation. some of the eminent Indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)
2)Define Tapetum?
A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei.
3)Define Endothecium.
A:It is remarkably identified by their radially elongated structure.It is rarely multilayered and it produces "fibrous bands" which helps in time of anther dehiscence.
4)Define Microspore?
A:It is formed by microsporogenesis and is responsible for the development of male gametophyte .These are the results of meiosis and usually smaller in size. 5. What is Palynology?
Ans. Palynology is the study of external morphology of pollen grains and spores .
6. What is Megasporangium ? Mention the types.
Ans. The formation of four haploid megaspores from megaspore mother cell through meiosis.
The types are :
1. Linear
2. T-shaped
3. Inverted T-shaped
4. Isobilateral
7. Define Monosporic, Bisporic, Tetrasporic.
Ans. Monosporic: The embryo sac which is derived from only one of the four megaspore.
Bisporic: The functional megaspore is developed from two megasporenuclei.
Tetrasporic: All the four nuclei of the take part in the formation of tetrasporic embryo sac.
8. Define fertilization. Who coined the term syngamy.
Ans. The fusion of male gamete with the female gamete is known as fertilization. Syngamy term was coined by Stras burger(1884).
9. Define Double fertilization and Triple fusion.
Ans. In angiosperms, the two main gametes relased in to the embryo sac take part in fertilization. One of the sperm fuses with the egg nucleus resulting in a zygote. The other male gamete fuses with the secondary nucleus. This is known as double fertilization.
Triple fusion: The union of one male nucleus with secondary nucleus is known as triple fusion. As it involves the union of three nuclei the resultant is called primary endosperm nucleus.
10. What is Endosperm and its types?
Ans. Endosprerm is most nutritive tissue for the developing embryos in angiosperms.
There are three types:
1. Nuclear Endosperm
2. Cellular Endosperm
3.Heleboidal Endosperm
Mam this is Sri Ram NB-55 this is my second part of my assigment
ReplyDelete11. What is Ruminate Endosperm?
Ans. Mature endosperm with some degree of irregularity and unevenness in its surface is called Ruminate endosperm.
12. What is Helobial Endosperm?
Ans. The primary endosperm nucleus moves towards the chalazal end of the embryo sac. Here it divides to form a large micropylar chamber and a small chalazal chamber.
13. Difference between dicot and monocot embryos.
Ans. Dicot: There are two cotyledons attached to embryonal axis.
Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present.
14. What is Scutellum?
Ans. The single cotyledon of a monocot embryo is known as Scutellum
15. Define polyembryony?
A. the production of more than one embryo from one egg is known as polyembryony. Polyembryony, a condition in which two or more embryos develop from a single fertilized egg, forming what in humans is known as identical twins. A common phenomenon in many plant and animal species, polyembryony occurs regularly in the nine-banded armadillo, which usually gives birth to four identical young.
DEAR Sri Ram NB-55,
DeleteGOOD
Hi good evening Mam this is Byri Ravali NB-43(172443)
ReplyDelete1)Define Embrology? ? name eminent indian embryologists?
A:It is the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation.
some of the eminent indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)
2)Define Tapetum?
A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei.
3.Define Endothecium?
A. This is a transverse section of the anther, the part of the stamen that actually produces the pollen grains. As part of pollen development, the cells lining the anther lumen – a layer known as the endothecium – secretes materials that are essential for the proper maturation of the pollen grains.
it is the fibrous tissue present in the middle layer of anther.
4. What is Microspore ?
Ans. Microspore is the pollen grain of seed plant.
5. What is Palynology?
Ans. Palynology is the study of external morphology of pollen grains and spores .
6. What is Megasporangium ? Mention the types.
Ans. The formation of four haploid megaspores from megaspore mother cell through meiosis.
The types are :
1. Linear
2. T-shaped
3. Inverted T-shaped
4. Isobilateral
7. Define Monosporic, Bisporic, Tetrasporic.
Ans. Monosporic: The embryo sac which is derived from only one of the four megaspore.
Bisporic: The functional megaspore is developed from two megasporenuclei.
Tetrasporic: All the four nuclei of the take part in the formation of tetrasporic embryo sac.
8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.
9. Define double fertilisation and triple fusion?
A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.
10. Define endosperm? mention the types in it.
A. a nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.
DEAR Byri Ravali NB-43,
DeleteGOOD
I am G. Saibhargav NB-26 submitting my botany assignment.
ReplyDelete1.Define embrology. Name the imminent Indian embryologists. Ans. Embryology is the branch of biology that studies the prenatal development of gametes, fertilization, and development of embryoes and fetuses. The imminent Indian embryologist is Panchanan Maheswari. 2. What is tapetum? Ans. Tapetum is the inner most layer of anther wall and completely surrounds the sporogenous tissue. 3. What is Endothecium? Ans. Endothecium is the layer of cells present inner to epidermis in anther wall. 4. What is Microspore ? Ans. Microspore is the pollen grain of seed plant. 5. What is Palynology? Ans. Palynology is the study of external morphology of pollen grains and spores . 6. What is Megasporangium ? Mention the types. Ans. The formation of four haploid megaspores from megaspore mother cell through meiosis. The types are : 1. Linear 2. T-shaped 3. Inverted T-shaped 4. Isobilateral 7. Define Monosporic, Bisporic, Tetrasporic. Ans. Monosporic: The embryo sac which is derived from only one of the four megaspores. All the nuclei in such embryo sac are genetically identical, because they are derived through mitoses of a single nucleus. Bisporic: The first meiotic division in megaspore mother cell results in two dyad cells. Only one of the dyad cells undergoes the second meiotic division, but no wall formation occurs. So the resulting two megaspore nuclei contribute in the formation of embryo sac. Tetrasporic: All the four nuclei of the coenomegaspore take part in the formation of tetrasporic embryo sac. In this type there is no wall foramtion. 8. Define fertilization. Who coined the term syngamy. Ans. The fusion of male gamete with the female gamete is known as fertilization. Syngamy term was coined by Stras burger(1884). 9. Define Double fertilization and Triple fusion. Ans. In angiosperms, the two main gametes relased in to the embryo sac take part in fertilization. One of the sperm fuses with the egg nucleus resulting in a zygote. The other male gamete fuses with the secondary nucleus forming primary endosperm nucleus. This is known as double fertilization. Triple fusion: The union of one male nucleus with secondary nucleus is known as triple fusion. As it involves the union of three nuclei the resultant is called primary endosperm nucleus. 10. What is Endosperm and its types? Ans. Endosprerm is most common nutritive tissue for the developing embryos in angiosperms. There are three types: 1. Nuclear Endosperm 2. Cellular Endosperm 3. Helobial Endosperm 11. What is Ruminate Endosperm? Ans. Mature endosperm with some degree of irregularity and unevenness in its surface contour is called Ruminate endosperm. 12. What is Helobial Endosperm? Ans. The primary endosperm nucleus moves towards the chalazal end of the embryo sac. Here it divides to form a large micropylar chamber and a small chalazal chamber. 13. Difference between dicot and monocot embryos. Ans. Dicot: There are two cotyledons attached to embryonal axis. Coleoptile is absent. Scutellum is absent. Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present. 14. What is Scutellum? Ans. The single cotyledon of a monocot embryo is known as Scutellum
15. What is Polyembryony ? Ans:The occurence of more than one embryo in a seed is known as polyembryony. 16. Mention the objectives of polyembyrony. Ans:1. cleavage of the embryo. 2. formation of embryosacs form other cells of the embryosacs. 3. for the development of one than one embryosac within the same ovule.
Hi mam this is Ravali NB-43 and this is the second part of my assigment
ReplyDelete11. Define ruminate endosperm?
A. the condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms. it is the tissue produced inside the seeds of most of the flowering plants following fertilization. It surrounds the embryo and provides nutrition in the form of starch, though it can also contain oils and protein.
12. Define Helobial type of endosperm?
A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.
13. Difference between dicot and monocot embryos.
Ans. Dicot: There are two cotyledons attached to embryonal axis. Coleoptile is absent. Scutellum is absent.
Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present.
14. What is Scutellum?
Ans. The single cotyledon of a monocot embryo is known as Scutellum
15. Define polyembryony?
A. the production of more than one embryo from one egg is known as polyembryony.
DEAR G. Saibhargav NB-26,
DeleteGOOD
I am Hepsiba NB-51. Submitting my botany assignment.
ReplyDelete1.define embroyology? name eminent indian embryologists?
A.the branch of biology and medicine concerned with the study of embryos and their development.
samo of the eminent indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)
2.Define Tapetum?
A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.
3.Define Endothecium?
A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.
4.Define microspore?
A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.
5. Define Palaenology?
A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.
6. Define megasporangium? and mention types in it?
A. the structure in certain spore-bearing plants in which the megaspores are formed.
Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.
7. define monosporic, bisporoic, tetrasporic types of embryo sac?
A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
1.monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
2.bisporic type: bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
3. tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.
8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.
9. Define double fertilisation and triple fusion?
A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.
10. Define endosperm? mention the types in it.
A. a nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.
DEAR Hepsiba NB-51
DeleteGOOD
I am Hepsiba NB-51 submitting the remaining part of my botany assignment.
ReplyDelete11. What is Ruminate Endosperm? Ans. Mature endosperm with some degree of irregularity and unevenness in its surface contour is called Ruminate endosperm. 12. What is Helobial Endosperm? Ans. The primary endosperm nucleus moves towards the chalazal end of the embryo sac. Here it divides to form a large micropylar chamber and a small chalazal chamber. 13. Difference between dicot and monocot embryos. Ans. Dicot: There are two cotyledons attached to embryonal axis. Coleoptile is absent. Scutellum is absent. Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present. 14. What is Scutellum? Ans. The single cotyledon of a monocot embryo is known as Scutellum
15. What is Polyembryony ? Ans:The occurence of more than one embryo in a seed is known as polyembryony. 16. Mention the objectives of polyembyrony. Ans:1. cleavage of the embryo. 2. formation of embryosacs form other cells of the embryosacs. 3. for the development of one than one embryosac within the same ovule.
DEAR HEPSIBA,
DeleteGOOD
Hi good evening mam this is Johanna NB-48
ReplyDelete1)Define Embrology? ? name eminent indian embryologists?
A:It is the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation.
some of the eminent indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)
2)Define Tapetum?
A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei.
3.Define Endothecium?
A. This is a transverse section of the anther, the part of the stamen that actually produces the pollen grains. As part of pollen development, the cells lining the anther lumen – a layer known as the endothecium – secretes materials that are essential for the proper maturation of the pollen grains.
it is the fibrous tissue present in the middle layer of anther.
4. What is Microspore ?
Ans. Microspore is the pollen grain of seed plant.
5. What is Palynology?
Ans. Palynology is the study of external morphology of pollen grains and spores .
6. What is Megasporangium ? Mention the types.
Ans. The formation of four haploid megaspores from megaspore mother cell through meiosis.
The types are :
1. Linear
2. T-shaped
3. Inverted T-shaped
4. Isobilateral
7. Define Monosporic, Bisporic, Tetrasporic.
Ans. Monosporic: The embryo sac which is derived from only one of the four megaspore.
Bisporic: The functional megaspore is developed from two megasporenuclei.
Tetrasporic: All the four nuclei of the take part in the formation of tetrasporic embryo sac.
8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.
9. Define double fertilisation and triple fusion?
A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.
DEAR Prashanth Kumar,
DeleteGOOD
Hi mam this is johanna NB-48 and this is my second part of my assigment
ReplyDelete10. Define endosperm? mention the types in it.
A. a nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.
11. Define ruminate endosperm?
A. the condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms. it is the tissue produced inside the seeds of most of the flowering plants following fertilization. It surrounds the embryo and provides nutrition in the form of starch, though it can also contain oils and protein.
12. Define Helobial type of endosperm?
A. It is an intermediate type between the nuclear and cellular types. The first division is accompanied by cytokinesis but the subsequent ones are free nuclear. The chamber towards micropylar end of embryo sac is usually much larger than the chamber towards chalazal end.
13. Difference between dicot and monocot embryos.
Ans. Dicot: There are two cotyledons attached to embryonal axis. Coleoptile is absent. Scutellum is absent.
Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present.
14. What is Scutellum?
Ans. The single cotyledon of a monocot embryo is known as Scutellum
15. Define polyembryony?
A. the production of more than one embryo from one egg is known as polyembryony.
DEAR johanna NB-48,
DeleteGOOD
This is M. Deepthi NB-53. This is my botany assignment on embryology.
ReplyDelete1.Define embrology. Name the imminent Indian embryologists. Ans. Embryology is the branch of biology that studies the prenatal development of gametes, fertilization, and development of embryoes and fetuses. The imminent Indian embryologist is Panchanan Maheswari. 2. What is tapetum? Ans. Tapetum is the inner most layer of anther wall and completely surrounds the sporogenous tissue. 3. What is Endothecium? Ans. Endothecium is the layer of cells present inner to epidermis in anther wall. 4. What is Microspore ? Ans. Microspore is the pollen grain of seed plant. 5. What is Palynology? Ans. Palynology is the study of external morphology of pollen grains and spores . 6. What is Megasporangium ? Mention the types. Ans. The formation of four haploid megaspores from megaspore mother cell through meiosis. The types are : 1. Linear 2. T-shaped 3. Inverted T-shaped 4. Isobilateral 7. Define Monosporic, Bisporic, Tetrasporic. Ans. Monosporic: The embryo sac which is derived from only one of the four megaspores. All the nuclei in such embryo sac are genetically identical, because they are derived through mitoses of a single nucleus. Bisporic: The first meiotic division in megaspore mother cell results in two dyad cells. Only one of the dyad cells undergoes the second meiotic division, but no wall formation occurs. So the resulting two megaspore nuclei contribute in the formation of embryo sac. Tetrasporic: All the four nuclei of the coenomegaspore take part in the formation of tetrasporic embryo sac. In this type there is no wall foramtion. 8. Define fertilization. Who coined the term syngamy. Ans. The fusion of male gamete with the female gamete is known as fertilization. Syngamy term was coined by Stras burger(1884). 9. Define Double fertilization and Triple fusion. Ans. In angiosperms, the two main gametes relased in to the embryo sac take part in fertilization. One of the sperm fuses with the egg nucleus resulting in a zygote. The other male gamete fuses with the secondary nucleus forming primary endosperm nucleus. This is known as double fertilization. Triple fusion: The union of one male nucleus with secondary nucleus is known as triple fusion. As it involves the union of three nuclei the resultant is called primary endosperm nucleus. 10. What is Endosperm and its types? Ans. Endosprerm is most common nutritive tissue for the developing embryos in angiosperms. There are three types: 1. Nuclear Endosperm 2. Cellular Endosperm 3. Helobial Endosperm 11. What is Ruminate Endosperm? Ans. Mature endosperm with some degree of irregularity and unevenness in its surface contour is called Ruminate endosperm. 12. What is Helobial Endosperm? Ans. The primary endosperm nucleus moves towards the chalazal end of the embryo sac. Here it divides to form a large micropylar chamber and a small chalazal chamber. 13. Difference between dicot and monocot embryos. Ans. Dicot: There are two cotyledons attached to embryonal axis. Coleoptile is absent. Scutellum is absent. Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present. 14. What is Scutellum? Ans. The single cotyledon of a monocot embryo is known as Scutellum
15. What is Polyembryony ? Ans:The occurence of more than one embryo in a seed is known as polyembryony. 16. Mention the objectives of polyembyrony. Ans:1. cleavage of the embryo. 2. formation of embryosacs form other cells of the embryosacs. 3. for the development of one than one embryosac within the same ovule.
DEAR DEEPTHI,
DeleteVERY CLUENGY.
WRITE QUESTION AND ANSWERS SEPARATELY
Good evening mam. I am G.Vineeta NB-47
ReplyDeleteQ1.Define embryology.Mention an eminent Indian embryologist?
Ans. Study of parental development of sex organs,fertilization and embryo.Eminent indian embryologist is PANCHANAN MAHESHWARI.
Q2.Define Tapetum?
Ans. Specialised layer of nutritive cells found within anther between sporogenous tissue and anther wall.Plays an important role in development of pollen grains and also source of precursor for pollen wall.
Q3.Define Endothecium?
Ans. The layer beneath epidermis in anther. As anther matures thickenings develop aiding in dehicdehis of anther wall and dispersal of pollen grains.
Q4. Define Microspores?
Ans. Land plant's spore that develope into male gametophytes which give rise to sperm cells that fertilize the egg to form zygote and develop into plant.
Q5.Define Palynology?
The study of pollen spores both in living and fossil forms is known as palynology.
Q6. Define megasporangium and it's types?
Ans. The female gametophyte is known ans megasporangium. Also known as integumented ovule. The types of megasporangium are 1. Orthotropic 2. Antropous 3. Hemianatropous 4. Camphylotropous 5. Amphitropous 6. Circinotropous.
Q7. Define monosporic,Bisporic and Tetrasporic type of embryosac?
Ans. Monosporic embryosac: Out of 4 haploid megaspores only 1 develops into female gametophyte and the other 3 degenerate. Eg.polygonum type
Bisporic embryosac: when two megasporic nuclei takes part in formation of embryosac. Both the nuclei are genetically different. Eg.allium type
Tetrasporic embryosac:In this type due to failure of cytokinesis I and II a four nucleate coenomegaspore tetrad is formed and all 4 nuclei participate in formation of embryosac. Eg.adoxa type,drusa type,peperomia type.
Q8. Define syngamy.Mention the scientists who coined the term?
Ans. The fusion of male and female gametes is known as syngamy or fertilization.Adolf Strasburger gave the term syngamy.
Good evening mam. This is second half of my assignment.NB-47. G.Vineeta
ReplyDeleteQ9. Define Double fertilization and Triple fusion?
Ans. Double fertilization: is a complex fertilization mechanism of flowering plants (angiosperms). This process involves the joining of a female gametophyte (megagametophyte, also called the embryo sac) with two male gametes
Triple fusion:The other male gamete pushes further into the embryo sac and fuses with the secondary nucleus and gives rise to a triploid nucleus called the primary endosperm nucleus
Q10.Define endosperm and mention it's type?
Ans.Endosperm is the name of food laden tissue which is meant for nourishing the embryo in seed plants.
Three main types of endosperm development in flowering plants are: (i) Nuclear type (ii) Cellular type and (iii) Helobial type.
Q11.Define ruminent endosperm?
Ans. Ruminate endosperm, the condition in which the endosperm is dissected by in-growths of the seed coat. Eg.Arecaceae
Q12.Define helobial endosperm?
Ans. This is an intermediate form between the other two types. In this type, Cell wall formation follows the first cell division. But the subsequent divisions do not lead to cell wall formation.
Eg. Monocotyledons
Q13. Difference between monocot and dicot embyros?
Ans.
The main difference between monocot and dicot is that monocot contains a single cotyledon in its embryo whereas dicot contains two cotyledons in its embryo.Monocot leaves show parallel venation and dicot leaves show reticulate venation. Monocot show fibrous root system dicots show tap root system.
Q14. Define scutellum?
Ans. It is the characterestic features of monocot only.The monocot consists of a large and shield shaped cotyledon known as scutellum.
it is involving in absorbing nutrients from the endosperm .
its other function is to transferiing it to the growing embryo during seed germination.
Q15. Define polyembryony?
Ans.The production of two or more embryos in one seed, due either to the existence and fertilization of more than one embryonic sac or to the origination of embryos outside of the embryonic sac. The production of two or more embryos in one seed, due either to the existence and fertilization of more than one embryonic sac or to the origination of embryos outside of the embryonic sac.
Q16. What are the objectives of polyembryony?
Ans. 1. cleavage of the embryo. 2. formation of embryosacs form other cells of the embryosacs. 3. for the development of one than one embryosac within the same ovule.
THANK YOU MAM.
I am B.Ravi Teja Nb_60
ReplyDelete)Define about tapetum?
A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei.
3)Define aboutEndothecium ?
A:It is remarkably identified by their radially elongated structure.It is rarely multilayered and it produces "fibrous bands" which helps in time of anther dehiscence.
I am B.Ravi Teja Nb_60
ReplyDeleteDefine microspore?
A. microspore refers to the spore produced by sporophytes. It is haploid and gives rise to a male gametophyte. Metagenesis or the alternation of generations involves the alternation of life phases in the life cycle of plants
I am B.Balaram Nb_20
ReplyDelete1.define embroyology? name eminent indian embryologists?
A.the branch of biology and medicine concerned with the study of embryos and their development.
samo of the eminent indian embryologists are:1. Johannes Peter Muller(1801-1858) 2. Julius Kollmann(1834-1918) 3. Hans Spemann(1869-1941)
2.Define Tapetum?
A. The tapetum is a specialised layer of nutritive cells found within the anther, of flowering plants, where it is located between the sporangenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains, as well as a source of precursors for the pollen coat.
3.Define Endothecium?
A. In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.
4.Define microspore?
A. Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote.
5. Define Palaenology?
A. Palynology is the study of plant pollen, spores and certain microscopic plankton organisms in both living and fossil form.
6. Define megasporangium? and mention types in it?
A. the structure in certain spore-bearing plants in which the megaspores are formed.
Megagametophytes of flowering plants may be described according to the number of megaspores developing, as either monosporic, bisporic, or tetrasporic. these are the types of megasporangium.
7. define monosporic, bisporoic, tetrasporic types of embryo sac?
A. Based on the number of megaspores, embryo sacs can be divided into three types: monosporic, bisporic, and tetrasporic.
1.monosporic type: it is also known as Polygonum-type embryo sac, meiosis of the diploid megaspore mother cell in the nucellus produces four haploid megaspores. Three of the megaspores, usually those at the micropylar end of the nucellus, subsequently undergo programmed cell death, leaving only one functional megaspore.
2.bisporic type: bisporic embryo sacs, meiosis produces only two megaspores, each containing two haploid nuclei, due to the absence of cytokinesis and cell plate formation following the second meiotic division. The megaspore nearest the micropyle then undergoes programmed cell death, leaving a single functional megaspore with two haploid nuclei.
3. tetrasporic type: In tetrasporic embryo sacs, cell plates fail to form after both meiotic divisions, resulting in a single four-nucleate megaspore.
8.define the terms fertilization and syngamy? and name the scientists who coined dthe names?
A. fertilisation: Fertilisation is fusion of gametes to form a new organism of the same species. Wilhelm August Oscar Hertwig(1849-1922) discovered fertilisation
syngamy: a method of reproduction in which two individuals (gametes) unite permanently and their nuclei fuse.Kondrashov coined the name. it is considered as the modified form of the fertilisation.
9. Define double fertilisation and triple fusion?
A. double fertilisation: fertilization characteristic of seed plants in which one sperm nucleus fuses with the egg nucleus to form an embryo and another fuses with polar nuclei to form endosperm.
triple fusion: the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant and results in the formation of the endosperm.
10. Define endosperm? mention the types in it.
A. a nutritive tissue in seed plants formed within the embryo sac by division of the endosperm nucleus. Three main types of endosperm development in flowering plants are: 1.Nuclear type. 2.Cellular type and 3.Helobial type.
I am B.Balaram Nb_20
ReplyDelete11. What is Ruminate Endosperm? Ans. Mature endosperm with some degree of irregularity and unevenness in its surface contour is called Ruminate endosperm. 12. What is Helobial Endosperm? Ans. The primary endosperm nucleus moves towards the chalazal end of the embryo sac. Here it divides to form a large micropylar chamber and a small chalazal chamber. 13. Difference between dicot and monocot embryos. Ans. Dicot: There are two cotyledons attached to embryonal axis. Coleoptile is absent. Scutellum is absent. Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present. 14. What is Scutellum? Ans. The single cotyledon of a monocot embryo is known as Scutellum
15. What is Polyembryony ? Ans:The occurence of more than one embryo in a seed is known as polyembryony. 16. Mention the objectives of polyembyrony. Ans:1. cleavage of the embryo. 2. formation of embryosacs form other cells of the embryosacs. 3. for the development of one than one embryosac within the same ovule.
Hello Mam,
ReplyDeleteIam Jayanth Muvvala{NB-16}
Here's submitting my Botany Assignment
.Define embrology. Name the imminent Indian embryologists.
Ans. Embryology is the branch of biology that studies the prenatal development of gametes, fertilization, and development of embryoes and fetuses. The imminent Indian embryologist is Panchanan Maheswari.
2. What is tapetum?
Ans. Tapetum is the inner most layer of anther wall and completely surrounds the sporogenous tissue.
3. What is Endothecium?
Ans. Endothecium is the layer of cells present inner to epidermis in anther wall.
4. What is Microspore ?
Ans. Microspore is the pollen grain of seed plant.
5. What is Palynology?
Ans. Palynology is the study of external morphology of pollen grains and spores .
6. What is Megasporangium ? Mention the types.
Ans. The formation of four haploid megaspores from megaspore mother cell through meiosis.
The types are :
1. Linear
2. T-shaped
3. Inverted T-shaped
4. Isobilateral
7. Define Monosporic, Bisporic, Tetrasporic.
Ans. Monosporic: The embryo sac which is derived from only one of the four megaspores. All the nuclei in such embryo sac are genetically identical, because they are derived through mitoses of a single nucleus.
Bisporic: The first meiotic division in megaspore mother cell results in two dyad cells. Only one of the dyad cells undergoes the second meiotic division, but no wall formation occurs. So the resulting two megaspore nuclei contribute in the formation of embryo sac.
Tetrasporic: All the four nuclei of the coenomegaspore take part in the formation of tetrasporic embryo sac. In this type there is no wall foramtion.
8. Define fertilization. Who coined the term syngamy.
Ans. The fusion of male gamete with the female gamete is known as fertilization. Syngamy term was coined by Stras burger(1884).
9. Define Double fertilization and Triple fusion.
Ans. In angiosperms, the two main gametes relased in to the embryo sac take part in fertilization. One of the sperm fuses with the egg nucleus resulting in a zygote. The other male gamete fuses with the secondary nucleus forming primary endosperm nucleus. This is known as double fertilization.
Triple fusion: The union of one male nucleus with secondary nucleus is known as triple fusion. As it involves the union of three nuclei the resultant is called primary endosperm nucleus.
10. What is Endosperm and its types?
Ans. Endosprerm is most common nutritive tissue for the developing embryos in angiosperms.
There are three types:
1. Nuclear Endosperm
2. Cellular Endosperm
3. Helobial Endosperm
Iam Jayanth Muvvala {NB-16}Continution of My Assignment
ReplyDelete11. What is Ruminate Endosperm?
Ans. Mature endosperm with some degree of irregularity and unevenness in its surface contour is called Ruminate endosperm.
12. What is Helobial Endosperm?
Ans. The primary endosperm nucleus moves towards the chalazal end of the embryo sac. Here it divides to form a large micropylar chamber and a small chalazal chamber.
13. Difference between dicot and monocot embryos.
Ans. Dicot: There are two cotyledons attached to embryonal axis. Coleoptile is absent. Scutellum is absent.
Monocot: Only one cotyledon attached to the embryonal axis. The envolpe of plumule is called coleoptile. Scutellum is present.
14. What is Scutellum?
Ans. The single cotyledon of a monocot embryo is known as Scutellum
15. What is Polyembryony ?
Ans:The occurence of more than one embryo in a seed is known as polyembryony.
16. Mention the objectives of polyembyrony.
Ans:1. cleavage of the embryo.
2. formation of embryosacs form other cells of the embryosacs.
3. for the development of one than one embryosac within the same ovule.
Thank you Mam
Jayanth Muvvala {Nb-16}
This Is Venkat Prasad {NB-45}
ReplyDelete)Define Embrology?
A:It is the branch of Biology that deals with the "study of embryos"but in general terms it include the sex organ development,male and female gametes formation,fertilization,endosperm and embryo formation.
2)Define Tapetum?
A:The innermost layer that attain the level of maximum maturity during pollen-tetrad stage.It is composed of a single layer of cells and is characterised by the presence of dense cytoplasm and prominent nuclei.
3)Define Endothecium.
A:It is remarkably identified by their radially elongated structure.It is rarely multilayered and it produces "fibrous bands" which helps in time of anther dehiscence.
4)Define Microspore?
A:It is formed by microsporogenesis and is responsible for the development of male gametophyte .These are the results of meiosis and usually smaller in size.
5)Define Palynology?
A:The shape,size of microspore or pollengrain.Exine miscrosculpturing and number position character of aperture are great taxonomic importance.These are study under seperate branch called "Palynology".
6)What is Megasporangium and mention its types.
A:Megasporangium is a structure in angiosperm that produces female gametophytes called megaspores.It is borne in pairs at the base of scales of the cones.It is also called "ovule".
TYPES:
a)Orthotropous ovule
b)Anatropous ovule
c)Hemianatropous ovule
d)Campylotropous ovule
e)Amphitropous ovule
f)Circinotropous ovule.
7)Define Monosporic,Bisporic,Tetrasporic embryosacs.
A:Monosporic embryosac:In this type of embryo development 3 megaspores of tetrad gets degenerate and one remain functional and forms embryosac.
Bisporic embyrosac:When 2 megasporic nuclei takespart in the formation of embryosac.Both the nuclei are genetically different.
tetrasporic embryosac:In this type,due to failure of cytokinesis 1 and 2 a four nucleate coenomegaspore tetrad is formed and all 4 nuclei participate in the formation of embryosac.
8)Define Fertilization.Who coined the term "Fertilization".
A:It is a process in sexual reproduction that involves the union of male and female gametes to produce a zygote.The term fertilization was coined by"Oscar Hertwig"(1876).
This Is Venkat Prasad {NB-45}continution of my assignment
ReplyDelete9)Define a)"Double fetilization" or "Syngamy"and b)"Triple fusion".
A:a)Double fertilization:It is the process in which 2 male gametes fuse with the female gamete and the secondary nucleus respectively to form the zygote and the endosperm.
b)Triple fusion:It can be defined as the fusion involving two polar nuclei and a sperm nucleus that occurs in double fertilization in a seed plant,giving rise to triploid nucleus called "primary endosperm nucleus"(PEN),which later develops into the endosperm.
10)Define Endosperm and mention its types.
A:The endosperms are very vital parts of the fertilized embryo.An endosperm forms the surrounding tissue of the growing embryo.The primary endosperm nucleus divides repeatedly.It forms polyploidy nutritive tissue called endosperm.These are of 3 types.
They are: 1)Nuclear type
2)Cellular type
3)Helobial type
There is a special type of endosperm called as Ruminate endosperm.
11)Define Ruminate type of endosperm.
A:The condition in which the endosperm is dissected by ingrowths of the seed coat,is a common condition in palms.Ruminate endosperm forms when the seed coat intrudes inward via meristematic growth.
12)Define Helobial endosperm.
A:This type of endosperm occurs in the order "Helobiales".In this case,first division of primary endosperm nucleus is followed by a transverse wall.This wall divide the embryo sac into a small chalazal chamber and a large micropylar chamber.Then the nuclei in each chamber divide by free nuclear divisions.But,there are few nuclear divisions in the chalazal chamber.The endosperm in this chamber degenerate.Walls develop between nuclei in micropylar chamber.It produces cellular endosperm.
13)Mention the differences between Dicot and Monocot embryo.
A:Dicot embryo:An embryo with 2 cotyledons and plumule is distal.Coleoptile,Coleorhiza are absent and Scutellum is also absent.
Monocot embryo:An embryo with 1 cotyledon and plumule is lateral.Coleoptile,Coleorhiza are present and scutellum is present.
14)Define Scutellum.
A:It is the characteristic features of monocot only.The monocot consists of a large and shield shaped cotyledon known as "Scutellum".
15)Define Polyembyrony.
A:The formation of more than one embryo from a single fertilized ovum or in a single seed.
16)Mention the objectives of "Polyembryony".
A:Objectives of Polyembryony:
1)To determine whether polyembryony confers a competitive advantage to V.rossicum.
2)Assess whether this advantage,if present,is more pronounced in intra or interspecific competition, and
3)To determine whether the competitive advantage ,if present,is proportional to the number of embryos per seed.